INFN - Laboratori Nazionali di Frascati, May 1995

From: The Second DAFNE Physics Handbook

Chapter 10: Two Photon Initiated Processes

Eds. L. Maiani, G. Pancheri, N. Paver

Supported by the INFN, by the EC under the HCM contract number CHRX-CT920026 and by the authors home institutions.

Measurement of Two Photon Interactions with the KLOE Small Angle Tagging System

cm F. Anulli, R. Baldini-Ferroli, M. Bassetti,
S.Bellucci, A. Courau, I. Cohen, A. Moalem, G. Pancheri,
M. Preger, L. Razdolskaja, P. Sergio and A. Zallo

cm 1) Laboratori Nazionali di Frascati dell' I.N.F.N., I-00044 Frascati, Italy
2) Laboratoire de l'Accelerateur Lineaire, CNRS-IN2P3
Universite de Paris-Sud, 91405 Orsay, France
3) School of Physics and Astronomy, Tel-Aviv University Raimond and Beverly Sackler
Faculty of Exact Sciences - 69978 Tel Aviv, Israel
4) Department of Physics, Ben-Gurion University, 84105 Beer-Sheva, Israel

cm

Abstract:

The two-photon processes , expected in collisions at DANE, can be studied with high precision by introducing a small angle tagging facilities for the scattered electrons. We describe the design of the KLOE small angle tagging system to study interactions at DANE. This includes a COIL detector to tag particles hitting the SFM coils, a SAT detector to tag electrons passing through the SFM and a BREM detector for high energy photons in coincidence with tagged electrons in order to reject the radiative Bhabha events. Two such systems placed symmetrically with respect to the interaction point allow tagging both electrons and positrons. The maximum number of events/year that can be collected by this tagging system and the statistical error on the cross section are also discussed.

• 1 Introduction
• 2 Cross-sections for hadron production
• 3 The small angle tagging system
  • 3.1 The SAT detector
  • 3.2 The COIL detector
  • 3.3 Background contamination
• 4 Measurement of the cross section
• 5 Conclusions
• References